I recently had this off on my Dolphin and noticed the games weren't using all CPU up, but with this on It uses it 100% and I gain a massive boost in game speed. (Some games I can even play full speed, Gotcha Force, games like Kirby Air ride and Melee are almost 100%)

Can I have a Explanation on this? Does Dual Core Enable check box do something else besides Just activating Dual core?

I'm not a dev so I don't know for sure if this is the case, but my guess would that since dual core splits dolphin into two treads(one being the cpu emu and the other gpu) allows the computer to prioritize the threads differently and might even allow for greater speed increases on hyperthreading cpus that allow more than one process on each cycle.

You probably have a single core with hyperthreading technology. (Like a P4) Hyperthreading allows for multiple threads to be run simultaneously, which allows for a greater throughput of data, which means more speed. but programs have to be specifically written to use it. It kind of tricks the OS and apps into thinking it IS a dual core.

This is what Dolphin's Dual Core option does, puts the CPU emulation on one thread, and GPU emulation on another. So just because your computer has a single core, doesn't necessarily mean you can't benefit from the Dual Core option.

I think the name of the option Dual Core should be changed to Dual Thread, because it's not truly Dual Core technically. On my quad core i7, I boot Dolphin up and it says I have 16 cores. This is obviously not true, It does have 16 Threads though because of Hyperthreading. My CPU utilization doesn't go over 13% when running Dolphin because of this.

hyperthreading is not better than a real dualcore afaik.
only maybe in special cases where 2 threads share the same information.
dolphin (PPC emulation) i think could be one of that cases... but i cant check it due to lack of HT ^^)

OMG Thank you for bringing this topic up, because of this I spent 20 minutes looking up what the hell you were talking about, later to realise that my computer supports hyper-threading. Thank you so much!